Production of paper or like cartons or receptacles



9, 9. c. J. WILSON 1,870,977

PRODUCTION OE PAPEH 0R LIKE CARTONS OR RECEPTACLES Filed Juiy 10, 1930Patented Aug. 9, 1932 UNITED STATES. PATENT OFFICE CYRIL JOSEIEH WILSON,OF EDGBASTON, BIRMINGHAM, ENGLAND, ASSIGNOIR, TO ASSO- CIATED ICE &,DAIRIES LIMITED, 01 MANCHESTER, ENGLAND, A BRITISH COMPANY PRODUCTION OFPAPER 03 LIKE CARTONS OR RECEPTACLES Application filed July 10, 1930,Serial No. 467,051, and in Great Britain July 13, 1929.

' This invention has reference to paper, cardboard or like cartons,receptacles or containers (such as used for containing milk) of the kindthat comprise a tubular body which is produced by the formation of atube from an appropriately-shaped blank, one edge of which is gummed orglued to en able the making of a lap joint by the application ofpressure to the outside of the region of jointure after the ungummededge has been made to overlap the gummed edge by a body-forming machine.In the case of milk-cartons of this kind the body is completed bysecuring a bottom or closure to one end, dipping the same in molten waxor the like, or otherwise coating or proofing the interior with such waxto render the carton liquid-tight and to internally, seal the joint.

But according to the usual method of production, the strip of gum orother adhesive used for securing together the overlapping edges of thebody-blank is either applied to the whole width of the overlap, or maybe caused to spread over the said whole width under the pressure used inmaking the joint, so that there is always .the risk or possibility ofsome of the adhesive exuding or being displaced beyond the region of jointure into the interior, and onto the exterior, of the tube, and ofthis exuded or displaced adhesive not being adequately isolated from theeventual contents of the carton by the internal waxing. The exuding ofgum onto the outside of the tube is also objectionable.

The principal object of the present invention is to provide for themaking of internally-waxed or proofed carton or container bodies in amanner which ensures the complete'or adequate isolation of the jointingadhesive from the interior of the tube and from the eventual contents ofthe carton,

this object being realized according to the said invention by making thegummed or glued joint in such a manner that, in the completed joint, :1web or substantial width of the underlap edge of the body blank is leftfree of, or kept unattached or ungummed to, the overlap edge along theinside of the formed tube. That is to say, the adhesivev is so applied,and the joint is so made, that the spread of the said adhesive under thej oint-making pressure is limited or restricted to the region of theoverlap nearest the outside of the tube, leaving a substantial width ofthe underlap material, inwards of the gumming, loose or unconnected, sothat when the tube is subsequently dipped or treated with wax or otherproofing, the molten or fluid wax or the like is permitted accessbetwe-en'the unattached web or strip of underlap and the correspondingportion of the overlap so that the said wax, onhard ening or setting,makes, along the whole length of the joint, a sealing-strip of suchsubstantial thickness and/or width as adequately to isolate the adhesivematerial, orto interpose an adequate barrier of waxor proofing materialbetween the adhesive and the interior of the tube.

With reference to the accompanying draw- I Fig. 1 shows a carton bodymade according to this invention, parts being broken away to show themanner of sealing.

Fig. 2 is a section of the joint before waxng.

Fig. 3 is a section on an enlarged scale,

showing the joint as completed by the interv the body and 1) representsthe strip or length of gum-isolating wax between the said gum med regionand the inside of the said body.

A joint of this kind may be made by applying a relatively-narrow stripof gum or adhesive along a width of the underlap portion of thebody-forming blank at a substantial distance inwards of and parallelwith the edge of the said underlap. The width of the strip of gum asfirst applied, and its distance from the extreme edge of the under-lap,are so predetermined as to ensure that the spread of the um under thejoint-making pressure Will still leave free or unattached from theoverlap, a width of the underlap material sufiicient to provide for theeventual adequate wax-sealing or isolation of the adhesive from theinside of the tube. gum is applied so as to safeguard against spreadingto the outside of the formed tube under the sealing pressure, which maybe done by allowing the gum to become partly dry or tacky before sealingpressure is applied to the joint. i

. For example, and as shown in Figures 2 and 3 the carton body-blank maybe shaped in a rotary machine which is adapted to grip the edge e of theportion a of the blank that constitutes the underlap of the joint sothat, on completion of the body-forming operation, an in-turned lip isleft along the said edge Prior to the shaping operation, a strip of gum(Z is applied to the outside of the blank at such a distance from theedge 0 that, after subjection to the joint-making pressure, the spreadof the gum in the inward direction will still leave free or unattachedfrom the overlap e a strip of the underlap c, inwards of the gumming, asshown in Figure 2. Consequently, when the inside of the carton having abody-joint made as described is internally waxed or treated with, moltenproofing material, the said wax is enabled to permeate, and eventuallyset or harden, between the free strip of underlap and the overlap, andso form the wax barrier 7 for isolat-' ing the adhesive from theinterior-of the carton.

Where the body is formed on a machine having a stationary mandril, themandril may. as shown in Figure 4, be formed with a longitudinal recess7 so located that. at the moment when the joint-forming tool Itoperates, the said recess comes below the part of the underlap (inwards0f the gummed strip e) which is to be left free or unattached from theoverlap This enables, on the eventually internal waxing of the carton,the making of a lap-joint as shown in Figure 5, where the waxbarrier-strip that isolates the gum d from the inside of the carton isagain indicated by'g.'.

Having described my invention, what I claim and desire to secure byLetters Patent 18 1. A carton or container body of the kind referred towherein a substantial width and/or thickness or barrier of wax or thelike is interposed between the joint-forming adhesive and the interiorof the body.

2. A method of making carton and like bodies as claimed in claim 1, inwhich the.

joint-forming adhesive is so applied in relation to the edge of thejoint underlap as to leave a web or width of the said underlap free fromor unattached to the overlap and to pro- Preferably also the vide forthe formation of a barrier-stripof wax or proofing material between thead- CYRIL JOSEPH WILSON.

